diff --git a/libc/dns/getaddrinfo.c b/libc/dns/getaddrinfo.c
index 015cc61d5..0d6865b22 100644
--- a/libc/dns/getaddrinfo.c
+++ b/libc/dns/getaddrinfo.c
@@ -53,7 +53,7 @@ int getaddrinfo(const char *name, const char *service,
 
   if (!name && !service) return EAI_NONAME;
   if (!name && (hints->ai_flags & AI_CANONNAME)) return EAI_BADFLAGS;
-  if (service) {
+  if (service && (port = parseport(service)) == -1) {
     if (hints->ai_socktype == SOCK_STREAM)
       strcpy(proto, "tcp");
     else if (hints->ai_socktype == SOCK_DGRAM)
@@ -62,9 +62,8 @@ int getaddrinfo(const char *name, const char *service,
       strcpy(proto, "");
 
     if ((port = LookupServicesByName(service, proto, sizeof(proto), NULL, 0,
-                                     NULL)) == -1) {
-      if ((port = parseport(service)) == -1) return EAI_NONAME;
-    }
+                                     NULL)) == -1)
+      return EAI_NONAME;
   }
   if (!(ai = newaddrinfo(port))) return EAI_MEMORY;
   if (service) ai->ai_addr4->sin_port = htons(port);
diff --git a/libc/dns/prototxt.c b/libc/dns/prototxt.c
index 5195deeed..e974ab442 100644
--- a/libc/dns/prototxt.c
+++ b/libc/dns/prototxt.c
@@ -67,7 +67,7 @@ static textwindows noinline char *GetNtProtocolsTxtPath(char *pathbuf,
  * @param bufsize is the size of buf
  * @param filepath is the location of the protocols file
  *          (if NULL, uses /etc/protocols)
- * @returns 0 on success, -1 on error
+ * @return 0 on success, -1 on error
  *
  * @note aliases are not read from the file.
  */
@@ -129,7 +129,7 @@ int LookupProtoByNumber(const int protonum, char *buf, size_t bufsize,
  * @param bufsize is the size of buf
  * @param filepath is the location of protocols file
  *          (if NULL, uses /etc/protocols)
- * @returns -1 on error, or
+ * @return -1 on error, or
  *          positive protocol number
  *
  * @note aliases are read from file for comparison, but not returned.
diff --git a/libc/dns/servicestxt.c b/libc/dns/servicestxt.c
index 8784fa11d..24742066a 100644
--- a/libc/dns/servicestxt.c
+++ b/libc/dns/servicestxt.c
@@ -72,7 +72,7 @@ static textwindows noinline char *GetNtServicesTxtPath(char *pathbuf,
  * @param bufsize is the size of buf
  * @param filepath is the location of the services file
  *          (if NULL, uses /etc/services)
- * @returns 0 on success, -1 on error
+ * @return 0 on success, -1 on error
  *
  * @note aliases are not read from the file.
  */
@@ -149,7 +149,7 @@ int LookupServicesByPort(const int servport, char *servproto,
  * @param bufsize is the size of buf
  * @param filepath is the location of services file
  *          (if NULL, uses /etc/services)
- * @returns -1 on error, or
+ * @return -1 on error, or
  *          positive port number
  *
  * @note aliases are read from file for comparison, but not returned.
diff --git a/libc/sock/parseport.c b/libc/sock/parseport.c
index 0a215b747..4b9d1b65f 100644
--- a/libc/sock/parseport.c
+++ b/libc/sock/parseport.c
@@ -20,7 +20,17 @@
 #include "libc/sock/sock.h"
 #include "libc/sysv/errfuns.h"
 
-int parseport(const char *service) {
-  int port = atoi(service);
-  return (0 <= port && port <= 65535) ? port : einval();
+/* parses string to port number.
+ *
+ * @param service is a NULL-terminated string
+ * @return valid port number or einval()
+ *
+ * @see strtoimax
+ */
+int parseport(const char* service) {
+  char* end;
+  int port = strtoimax(service, &end, 0);
+  if (!service || end == service || *end != '\0' || port < 0 || port > 65535)
+    return einval();
+  return port;
 }